1. Field of the Invention
The present invention relates to an insulating system, such as a footwear system, with moisture transport properties including an insulating batting and a fabric lining. The insulating system or footwear system may have antimicrobial efficacy, due to the fact that the insulating batting may also comprise antimicrobial fibers and/or the fabric lining may also have antimicrobial efficacy. The invention also relates to a footwear or insulating system including a non-woven densified material.
2. Description of the Related Art
There has been increased interest in recent years in incorporating additional performance features into footwear and garments beyond that of insulating and cushioning materials. To this end, developments in moisture management assemblies and anti-microbial treatments for footwear materials have been pursued.
WO 98/28476, discloses utilizing Eastman 4DG transport fibers in non-woven applications for footwear. The WO 98/28476 application discloses use of a nonsymmetrical multi-grooved transport fiber. WO 98/28476 shows that this fiber is insufficient in use due to pilling and durability in use. WO 98/28476 claims as an improvement to this product a non-woven felt liner which is designed to be a replacement liner. This liner is a thermal bonded (binder fiber addition) version of 4DG (and CoolMax) needled to a density of 150-160kg/m3. However, this high density felt produces a product which does not have good moisture transport properties. Moreover, this is very stiff product, which has to be very thin, and is thus not particularly durable.
There is thus a continuing desire to provide materials and systems having improved insulating and/or moisture transport properties.
In accordance with these needs, the present invention provides a system that includes an insulating layer, which has moisture transport properties, coupled to a liner fabric with transport properties, which can be tailored, for example, by appropriate selection of materials, for higher wear durability than the regular non-woven liner of the prior art. Antimicrobial efficacy can also be obtained by adding antimicrobial treatments to the insulation and/or the liner, where the treatments could be antimicrobial fibers, applications, or other technologies.
According to the present invention, there is provided an insulating system for garments such as footwear and other articles in which an insulating system is desirable, hereunto referred to as the insulating system. The insulating layer component of the insulating system is characterized as a non-woven of a density of about 40 to 90 kg/m3 and composed of fibers that are of cruciform cross section, being either untreated or treated with a silicone surface modifier, are combinations of either untreated or treated with a silicone surface modifier cruciform cross section fibers and antimicrobial fibers, are combinations of untreated and treated with a silicone surface modifier cruciform cross section fibers, are combinations of untreated and treated with a silicone surface modifier cruciform cross section fibers and antimicrobial fibers, or all of the above variations combined with thermal binding fibers in a proportion of from about 0% to about 25%. The antimicrobial agents discussed above may be combined with the silicone surface modifier. Although the present invention preferentially uses polyester, such as poly(ethylene) terephthalate, as the cruciform fibers, the cruciform fibers could alternatively be produced from polyamide, polyolefin, aramids or other fibers that can be produced in cruciform or other cross sections, with, for example, grooves or lobes, allowing for the transport of water. The lining component of the system is characterized in that the liner has moisture transport properties, or that the liner has moisture transport properties and antimicrobial properties.
When used in footwear, the insulating system is preferably the innermost layer of the footwear construction. The liner fabric is preferably the part of the footwear which comes in contact with a foot or sock.
The system is further characterized by an attachment mechanism, either mechanical such as sewing, thermal such as point and ultrasonic bonding, or chemical adhesive that allows moisture transport between the liner and insulating layer.
The invention also provides an insulating system which is a non-woven densified material, which comprises a wicking fiber, such as a polyester with a cruciform cross-section, a binder fiber, and an antimicrobial fiber or agent. This insulating system may be used as an insulating layer in garments and other articles in which an insulating system is desirable. For example, the insulating system may be used in footwear such as in the tongue, sole and/or vamp.
According to the invention, there is also provided a system comprising an insulating batting comprising a non-woven densified material, combined, by chemical, mechanical or thermal means, with an abrasion resistant fabric lining that exhibits moisture transport properties.
In another embodiment, the invention relates to footwear, apparel, or an insulating layer comprising a non-woven material that comprises a cruciform cross-section polyester fiber. In a preferred embodiment, the non-woven material is a densified material.
In another embodiment, there is provided a non-woven insulating system comprising a wicking fiber, a binder fiber, and an antimicrobial fiber or agent. Preferably, the wicking fiber comprises a polyester with a multilobed or a multigrooved cross section, such as a cruciform cross section.